NPPB and atrial fibrillation: Patients with NYHA class III/IV were older (P = 0.026), had more atrial fibrillation (P = 0.001), higher NT‐proBNP at baseline (P = 0.002) and follow‐up (P = 0.024) and lower stroke volume at follow‐up (P = 0.019) compared with those with NYHA class I/II (TableS1).